Research interests

Brief scientific biography

Alive classic of astronomy and astrophysics PhD Halton Christian Arp, as well as it is necessary for astronomers, was born at spring equinox, March 21, 1927 in New York, USA. In 1949 he has finished Harward getting bachelor degree with "laude". 4 years later he has got Philosophy Doctor degree in the Californian Technological Institute ("Caltech").

Since 1953 to 1955 he was employee of the Carnegie Center in Washington, since 1955 to 1957 he was in staff of the Indiana University. During 29 years Dr. Arp carried out scientific experiments in Mount-Wilson and Palomar observatories.

Working in these observatories he has made becoming classical "the Catalogue of Peculiar Galaxies" ("Arp's Catalogue" or "Atlas of Peculiar Galaxies of Arp"), where information on galaxies distinguished in "abnormality" that is diversion from usual spiral structure are gathered. In notations and references these galaxies have name of Arp + catalogue number.

At the begining of the scientific activity Dr. Arp was engaged in search of novae in М31 under leading of Edwin Hubble.

In 1983 he was invited to staff of Max Planck Astrophysical institute in Munich.

During a long time Dr. Arp studied peculiar galaxies.
Arp has collected a catalog of unusual galaxies titled Atlas of Peculiar Galaxies, which was first published in 1966 [9]. Arp realized that astronomers understood little about how galaxies change over time, which led him to work on this project. This atlas was intended to provide images that would give astronomers data from which they could study the evolution of galaxies. Arp later used the atlas as evidence in his debate on QSOs.
Today the astronomers recognize, that Arp has developed the excellent atlas of irregular and confluent galaxies. Ironically, many of these objects (particularly Arp 220) are also used as spectral templates for studying high-redshift galaxies.

One of major astronomical discovery of Dr. Arp is that the quasars or, in another words, quasi-stellar objects (QSO) are local objects ejected from the core of active galactic nuclei (AGN). The theory was originally proposed in the 1960s as an alternative to Maarten Schmidt's explanation for QSOs, which stated that they were very distant galaxies that appeared to be highly redshifted because of the expansion of the universe [1]. The implication of the hypothesis was that most of the observed redshift of these QSOs must have a non-cosmological or "intrinsic" origin. Arp has suggested that the QSO emission may instead be ejecta from active galactic nuclei. Nearby galaxies with both strong radio emission and peculiar morphologies, particularly M87 and Centaurus A, appeared to support Arp's hypothesis [2]. In his books, Arp has provided his reasons for believing that the Big Bang theory itself is wrong, citing his research into QSOs. Instead, Arp supports the redshift quantization theory for describing the redshifts of galaxies [3].

Since Arp originally proposed his theories in the 1960s, however, telescopes and astronomical instrumentation have advanced greatly; the Hubble Space Telescope was launched, multiple 8-10 meter telescopes (such as those at Keck Observatory) have become operational, and detectors such as CCDs are now more widely used. These new telescopes and new instrumentation have been used to examine QSOs further. QSOs are now generally accepted to be very distant galaxies with high redshifts. Moreover, many objects that are high-redshift counterparts to normal nearby galaxies have been identified in many imaging surveys, most notably the Hubble Deep Field[4]. Moreover, the spectra of the high-redshift galaxies, as seen from X-ray to radio wavelengths, match the spectra of nearby galaxies (particularly galaxies with high levels of star formation activity but also galaxies with normal or extinguished star formation activity) when corrected for redshift effects.[5 - 7]

Nonetheless, Arp has not wavered from his stand against the Big Bang and still publishes articles stating his contrary view in both popular and scientific literature, frequently collaborating with Geoffrey Burbidge and Margaret Burbidge.[8]

The awards and other honours

In 1960, Arp was awarded the Helen B. Warner Prize for Astronomy by the American Astronomical Society, a prize "normally awarded annually for a significant contribution to observational or theoretical astronomy during the five years preceding the award" [10]. And in the same year, Arp was awarded the AAAS Newcomb Cleveland Prize for his address, "The Stellar Content of Galaxies" read before a joint session of the American Astronomical Society and AAAS Section D [11].

In 1984, he was awarded the Alexander von Humboldt Senior Scientist Award [12].

References

Arp H. "Additional members of the Local Group of galaxies and quantized redshifts within the two nearest groups" (1987) Journal of Astrophysics and Astronomy (ISSN 0250-6335), vol. 8, Sept. 1987, p. 241-255.

Summarised Papers

Abstract - Previous analyses have shown companion galaxies aligned along the minor axis of M31. The alignment includes some galaxies of higher redshift than conventionally accepted for Local Group members. Here we look at the distribution of all high redshift objects listed in a 10 x 10 deg. area around M31. We find not only galaxies of higher redshift but also quasars along the minor axis of this brightest Local Group galaxy, Some are an unusual class of low z, quasar-galaxy. Previously observers had noted radio sources aligned along the minor axis of M31. The ejection directions of quasars from active galaxy nuclei is also along the minor axis within a cone of about 20 deg. opening angle. It is shown here that the quasar-like and higher redshift objects associated with M31 are relatively concentrated along this axis. M33 also falls closely along the minor axis of M31 and the famous 3C48 and similar redshift galaxy/quasars are seen along a line coming from this Local Group companion of M31. What appears to be dusty nebulosity has also been shown to exist along this extended line in the sky.

Abstract - A quasar search in the region of the active galaxy NGC 1097 yielded 31 quasars in 1984. After completion of the 2dF survey in 2004 the number of catalogued quasars just within 1 degree of the galaxy increased to 142. About 38 $pm$ 10 of these are in excess of average background values. The evidence in 1984 is confirmed here by an increasing density of quasars as one approaches NGC 1097. Quasars within 1 degree differ from the background by being significantly brighter. There also appear two elliptical rings or arcs of quasars at r 20'and 40'.

Abstract - The aim is to investigate the region of the sky around NGC4410/Mrk1325 for objects which are physically associated with this active, double nucleus galaxy. We use archived data to study the placement, brightness, X-ray properties and redshifts of objects within 60' of the bright, central galaxy. It is found that pairs of quasars are aligned across NGC 4410 which, if ejected from it, have equal and opposite ejection velocities and fall very close to the quantized Karlsson redshift peaks for quasars. X-ray sources and Abell galaxy clusters at higher redshifts appear elongated along directions away from NGC4410.

Abstract - It is shown that all of the 32 point X-ray sources which lie within about 10' of the centre of nearby galaxies, and which have so far been optically identified are high redshift objects - AGN or QSOs. Thus the surface density of these QSOs p similar or equal to 0.1 per square arc minute. Some of them were originally discovered as X-ray sources and classified as ultraluminous X-ray sources (ULXs), nearly all of which lie near the centers of active galaxies. We demonstrate that this concentration around galactic nuclei is of high statistical significance: the probabiliy that p that they are accidental lies in the range one in a thousand to one in ten thousand, and apparently this excess cannot be accounted for by microlensing.

The strong radio source 3C343.1 consists of a galaxy and a QSO separated by no more than about 0.25". The chance of this being an accidental superposition is conservatively ~1x10-8. The z=0.344 galaxy is connected to the z=0.750 QSO by a radio bridge. The numerical relation between the two redshifts is that predicted from previous associations. This pair is an extreme example of many similar physical associations of QSOs and galaxies with very different redshifts.

In the Great Observatories Origins Deep Survey, 243 redshifts of objects fainter than 25.5 mag. were observed. Remarkably, two of them turned out to be very high redshift at z = 4.800 and z = 4.882. Even more remarkably these two fell only 3 and 1.5 arcsec on either side of an emisssion line galaxy of z = .733.

Since the force of gravity varies as the square of the inverse distance between objects why not make the ultimate extrapolation and let the distance go to zero? You get a LOT of density. Maybe it goes BOOM! But wait a minute, maybe it goes in the opposite direction and goes MOOB! Whatever. Most astronomers decided anyway that this was the only source that could explain the observed jets and explosions in galaxies.